As the sophistication of new devices increases, designers and developers are recognizing that usability is a critical element of any successful product. Almost no users of a given device or application take the time to stop and read the instructions, if any instructions are even included. Many users also have expectations of how certain devices or applications should perform—whether or not that is how the device or application is designed to operate. When a device or application behaves unusually, even if only in certain situations, users may become frustrated and stop using the device or application, or even find a similar substitute device or application to use instead.